1. Field of Invention
This invention relates to farm equipment. More specifically, the invention discloses an improved arrangement of a continuous cut knife and off set guards for use with a combine.
2. Prior Art
Power operated combines have been widely used for the cutting agricultural products. These combines normally include reciprocating cutting teeth located on cutting knives which are secured to a reciprocating knife bar. The reciprocating knife bar is generally driven with power from the combine, a tractor or from a separate motor. Top and bottom guards or alternatively sickle guards may be secured to a support bar to protect the cutting teeth and assist in the cutting of the agricultural product. The combine assembly which incorporates these elements extends horizontally and laterally outward from the body of the combine and is generally close to the ground for cutting the agricultural product at the stalks.
Two distinct types of assemblies have been designed to overlay the cutting knives secured to the reciprocating knife. The first is a standard sickle guard with fingers which extend over and around the cutting surface of the cutting blade. See, for example, U.S. Pat. Nos. 1,326,339, 1,642,808, 2,024,309, 2,500,104, 3,162,991, 4,909,026 and 5,241,811. Each of these sickle guard systems cut agricultural products by the use of a "wedge" cut, sickle guards above and below the knife hold the products as the knife cuts the products creating a wedge type cut.
An alternative design uses similar reciprocating cutting knives but secures those knives down with hold downs. See, for example, U.S. Pat. Nos. 2,735,254, 3,199,279 and 4,520,618. In these cutter guard combine assemblies, the guards operate in conjunction with the cutter knife to cut the agricultural product by use of a "scissor" cut as opposed to the "wedge" cut used by other mechanisms.
U.S. Pat. No. 4,651,511 combines both the "wedge" cut with a "scissor" cut in its operation. In particular, the short fingers (25) operate in conjunction with the knife section (15) to produce the "scissor" cut while the long fingers (22 and 23) operate in conjunction with the knife section (15) to produce the "wedge" cut.
Over the years manufacturers of combine assemblies using cutter guards have standardized the relative position of the cutter guards with respect to the remaining elements of the combine assembly. The standard cutter guard provides spacing between the guard fingers which is equal to the spacing between the cutting teeth of the cutter knife. In some circumstances this space is 3 inches and in others it is 11/2 inches. Regardless of which size cutting knife is used, traditionally the fingers of the cutter guards are corresponding in size. Thus, if a 3 inch cutting knife is used, the distance between the tips of the cutter guards is also 3 inches. In addition, where a 3 inch spacing exists, there is also a standard 3 inch stroke by the reciprocating cutter bar, so that, traditionally, each cutting tooth alternatively moves between the fingers of the cutter guard. Traditionally, the end of a reciprocating cycle will place the tips of the fingers of the cutter guard halfway between the cutting teeth of the continuous cut knife of the combine, thus reducing the effectiveness of the cutting action.
While the prior art patents disclose sickle guards and top and bottom guards for the cutting of crops, there are still problems in the efficient cutting of crops. For example, the existing mechanisms do not allow for the efficient cutting of a crop by permitting multiple cuts for each stroke of the cutter bar. In addition, problems exist because crops may get clogged in conventional cutting mechanisms because of their inefficient design. Finally, because of the size of the space of the conventional opening between the cutter teeth of cutter bars, rocks and dirt or other undesirable materials can become wedged between the guards and the knife assembly, resulting in maintenance problems.
Therefore, it is an object of this invention to provide a continuous cut knife and offset guard assembly for use with a combine and other crop cutting machines.
It is a still further object of this invention to disclose a continuous cut knife and offset guard assembly for a combine which provides continuous cutting of agricultural products.
It is a still further object of this invention to disclose a continuous cut knife and offset guard assembly for a combine which permits additional cutting capability in comparison to conventional combines.
It is another object of this invention to provide a continuous cut knife and offset guard for use with a combine where the distance between the cutting teeth of the cut knife is approximately twice the distance between the fingers of the upper and bottom guards.
It is a still further object of this invention to disclose top and bottom guards wherein the top and bottom guard fingers are offset such that at the end of a reciprocating cycle, the cutting teeth will stop at a position which is in line with the fingers of the top and bottom guard.
It is a still further object of this invention to provide an arrangement of the cutting teeth of the cut knife with the top and bottom guards which continuously cleans the cutting teeth while the combine is in operation.
These and other objects and features of the present invention will become apparent to those skilled in the art from a consideration of the following detailed description, drawings and claims. The description along with the accompanying drawings, provides a selected example of construction of the device to illustrate the invention.